Sir Menzies Campbell, the former Liberal Democrat leader, has announced he is
standing down from parliament at the next general election.

The Fife North East MP, 72, said he had enjoyed a “good innings” at the Commons but his decision to retire in 2015 represents a major blow to his party’s hopes of holding the seat.

He made the announcement two days after it emerged that Michael Moore, a close ally, had been sacked as Scottish Secretary in a Government reshuffle.

Friends of Sir Menzies said he was “very upset at the treatment meted out to Michael”. Although he had previously decided to retire, they said: “Michael’s sacking convinced him that now was the right time to announce he is standing down.”

Sir Menzies, who is known as Ming, succeeded Charles Kennedy as Lib Dem leader in 2006 but only lasted 19 months until he stepped down the following year amid poor poll ratings.

However, he built a reputation as an expert in foreign and defence issues, serving on the Commons Foreign Affairs and Parliamentary Intelligence and Security select committees.

Sir Menzies said it had been an “enormous privilege” to serve as an MP for 26 years but “now is the time to start” making preparations for his retirement.

He told the BBC he was leaving because of his age as he will be 80 when the next Parliament is due to end. "I have had a good innings but it's time to give someone else a go,” he said.

Nick Clegg, who succeeded him as leader, said it was "a sad day for me, my party and British politics as a whole". The Deputy Prime Minister said: “Sir Menzies has been a towering presence in British politics for the past three decades. He has served this country and our party with unparalleled distinction.”

Although the Lib Dems will be protecting a 9,048 majority in Fife North East, Sir Menzies had a strong personal following and it is expected that the Tories and Scottish Nationalists will target the seat.

He first stood as a candidate for the Liberal Democrats seat in 1976, but did not win his constituency for 11 years.

In his first career as a sprinter, he held the UK 100 metres record from 1967-74 and ran in the 1964 Tokyo Olympics. He later became a QC, and spoke for his party on foreign affairs, defence and Europe for more than a decade.

Earlier this year, he was named a Companion of Honour in the Queen's Birthday Honours list, which cited him as "one of the most respected politicians of his generation".

Sir Menzies said he would maintain his links with the constituency through positions including his chancellorship of St Andrews University.